Centralized lubricating system



Sept. 30, 1952 TEAR- 2,612,237

CENTRALIZED LUBRICATING SYSTEM Filed April 15, 1950 2 SHEETS SHEET 1agar 71341.5

Sept. 30, 1952 I 1 R, TEAR 7 2,612,237

CENTRALIZED LUBRICATING SYSTEM Filed April 15, 1950 2 SHEET S-SHEET 2 WVjam/072- fig ' Qdrw Patented Sept. 30, v l 1952 CENTRALIZED LUBRICATINGSYSTEM Harry R. Tear, Evanston, 111., assignor to Stewart- WarnerCorporation, Chicago, 111., a corporation of Virginia Application April15, 1950, Serial No. 156,076

This invention relates generally to centralized lubricating systems forintermittently supplying lubricant from a central source such as a highpressure pump to a number of remote bearings through charge measuring orfeeder valves located at the bearings. The invention has particularapplication to lubricating systems hav ing measuring or feeder valveswhich are operated by alternately supplying, lubricant at highpressureto the, valves and then substantially reducing or relieving thepressure. Application of pressure for a sufllcient time operates thevalves independently to supply measured charges of lubricant to thebearings, and reduction of the pressure'permits the valves to return tonormalin preparation for another lubricating cycle. Such'measuring ormetering valves require a feed conduit .or pipe line for supplyinglubricant from the source but do not require a separate return pipe.Lubricant under pressure is supplied to themeasuring valvesv byconnecting the conduit system with a high pressure pump. The pressure isrelieved by disconnecting or stopping the pump and venting the conduitsystemgto the atmosphere, whereupon a small amount of excess "lubricantis forced out of the conduit system through the venting means. Usuallythe excess lubricant is allowed to drain back into the pump reservoir.

Because of the viscosity of the lubricant, the venting of theconduitsystem may require a substantial timeintervah In lubricatingsystems having a large numberof-chargemeasuring valves and a longinterconnecting conduit systerm, the venting time, may impose anundesirable limitation upon the frequency with which lubricant chargesmay be supplied to the bearings. Furthermore, the venting time may set apractical limitupon the length of the conduit system and thereby uponthe extensiveness of the lubricating system. I I

This invention providesvalvingapparatus which may be interposed betweensuccessive sections of the conduit system to provide rapid venting ofthe more remote section.

Thus it is an object of this invention to provide an improved singlefeed pipe lubricating system.

Another object is to provide means for rapidly venting remote sectionsof an extensive lubricating system.

A further object is to provide means whereby more extensive lubricatingsystems are practicable than heretofore. I

A still further object is. to provide means be operated at frequentintervals.

10 Claims. (01. 184 -7) Other objects and advantages of this inventionand its underlying principles will appear from the following descriptiontogether with the drawings, in which: I

Fig. 1 shows diagrammatically an illustrative lubrication systemembodying the principles of this invention;

Fig.'- 2 is an elevational sectional view of an illustrative valveapparatus which may form a part. of the system of Fig. 1 to provideaccelerated venting; 7

Fig. 3 is an elevational sectional View of a modified vent acceleratingvalve; and

Fig. 4- is an elevational sectional view of another modified form of thevent accelerating valve.

In Fig. 1 a lubricant pump Ill draws lubrican through an intake pipe I!from a reservoir [2 and forces the lubricant under high pressure throughan outlet pipe l3 to an admitting valve it. The pump lubricant pressureof about 2500 pounds per square inch (p. s. 1.), for example. The pumpIll may be operated manually or may be power driven. 1

The admitting valve I4 has a control plunger is which may be operated toadmit lubricant The'lubricant flows outward through the feed line [8 andinto a plurality of lubricant metering valves 20 branching from theline. The metering valves 20 are connected individually with bearings(not shown) to be lubricated. When lubricant under suificient pressureis supplied to the valves 20, they operate to furnish predeterminedquantities of lubricant tothe bearings. The metering valves 20 may beconstructed as described in the United States Patent No. 2,205,- 320issued to Percy P. Teal, or as shown in the United States patentapplication of F. Schweisth al, Serial No. 570,961, filed January 1,i945, nowPatent Number 2,516,427, but other suitable valves may be used,of course.

After the valves 26 have been operated by lubricant pressure they areineffective to supply additional charges of lubricant to the bearingsuntil the lubricant pressure is reduced to a small amount. The reductionof pressure is accomplished by releasing the plunger l6 of the admittingvalve l4, and the valve then disconnects-the line I8 from thepump andconnects the line 3 with a vent pipe 22 which drains back into thereservoir l2.

It may develop a maximum According to this invention a plurality ofremote metering valves 26 are supplied by a second section 2 4 of thefeed line which is connected with the remote end of the first section l8of the feed line by a vent accelerating valve 26. When lubricant at highpressure is supplied by the pump to the first section [8 of the line,the accelerating valve 26 admits lubricant to the second section 24.When the lubricant pressure is released on the first section [8 of theline, the second section 24 is vented by the accelerating valve 26 intoan auxiliary reservoir or sump 28 open to the atmosphere. By providingadditional vent accelerating valves 26, 'a. third section of feed line(not shown) maybe supplied from the remote end of the second section 24,a fourth section (not shown) may be supplied from the remote end of thethird section, and so forth. The limit to the number of sections thusconnected is determined by the pressure required to force lubricant tothe. end. of. the system, which depends. upon. the size of the tubingused in the feed line. the kind of lubricant, and the temperature. I

Figs. 2, 3 and 4 illustrate threeforms of vent accelerating valveshaving body blocks 34. In Fig. 2 the first section of feed line 18communicates. through an inlet 36:with a cylindrical chamber or bore 46fitted with apiston.42. The piston 42 has a downwardly extending valverod 44 having its lower end shaped to provide lubricanttight engagementwith a. valve seat. 46. The piston 42 is urged upwardly by a helicalspring 48, and upward motionof the piston is arrested by engagement of apiston rod 58 with a plug 52 forming the upper wall of the chamber 48.The portion of the chamber 40 below the piston 42 communicates throughan opening 53 with the reservoir 28, which is in the form of a sump cupopen to the atmosphere and detachably secured to the valve 26 by bayonetconnections 54.

The first section I8 of feed linecommunicates with the second section ofline 24 through an outlet 58 and a passageway 60 closed by a ball checkvalve 62 which is urged upwardly against a valve seat 64 by a helicalspring 66.

The second section 24- of the feed line communicates with the portion ofchamber 40 below the piston 42 through a passageway which is closed whenthe valve 44 engages its seat 46'.

When lubricant under pressure is supplied by the pump Ill through thevalve l4 to the first section l8 of feed line, the lubricant pressurerapidly builds upin the upper part of the chamber 40 and in thepassageway 60. The pressure tends to force the piston 42 downward andthereby to compress the spring 48'and move the valve 44 into engagementwith the seat 46. Thelubricant pressure also tends to force the ballcheck valve 62 from its seat 64 and thereby to permit lubricant to flowinto the second section 24 of the line. The springs 48 and 66 aredesigned with relation to the areas of the piston 42 and the ball checkvalve 62, respectively, so that a somewhat greater lubricant pressure isrequired to, open the ball check valve 62 than is required to move thepiston 42 downward to close, the vent valve 46. Therefore, thepassageway 10 extending from the second section of line 24 through theventing valve 46 to the lower part of; the chamber 40 and thence to thereservoir 28 is closedv before lubricant is admitted. to the second linesection 24 from the passageway 60. For example, the piston 42 and spring48. may be proportioned to permit the vent valve to close 4 at some lowlubricant supply pressure, such as p. s. i., while the spring 66 andball check 62 are proportioned to permit the ball check to open at asomewhat higher pressure, such as p. s. i. After the ball check valve 62is opened, the lubricant flows freely into the second section of line 24and lubricant pressure builds up in the line 24 and in the passageway 70connecting with v the vent valve 44. However, the pressure in thepassageway 10 is ineffective to unseat the valve rod 44 because of thesmall area of the valve seat 46 compared with that of the piston 42.

When the first section [8 of the line is vented by operation or thevalve I6, the lubricant pressure in the chamber 40 and the passageway 60drops. Thecheck valve 62 closes to prevent reverse fiow of lubricantfrom the second section 24 of the line into the passageway 66.

The venting valve 44 remains closed until the force of the lubricantpressing on the piston 42 becomes lessthan the-sum of the force of thespring 48 and the force of the lubricant pressing on the valve rod 44.For example, if the area. of the piston 42 istwice that of the valveseat 46, the vent valve opens when the pressure in the chamber 40'approaches one-half the pressure in the passageway 10,. and venting ofthe second section 24 of" the linebegins. Each time the line section,v241, isvented. a small quantity of lubricant drains into the sump 28. Atrelatively infrequent intervals the sump 28 may be detached from thevalve 26.. and emptied into the main reservoir I2.

Fig. 3 illustrates a modified form of the vent accelerating valveillustrated inv Fig. 2. In most respects the valve of'Fig. 3 is similarto that of Fig. 2, and corresponding parts bear the same referencecharacters. valve chamber 88 is interposed between the venting valvechamber 40 and the passageway 60. A piston 82' is fitted into thechamber and a helical spring 841 urges the piston to the left so that avalve rod 86 extending from the piston normally engages a seat 88 toclose an opening 90 connecting. the venting valve chamber 40 with theadmitting valve chamber 80. The portion of the chamber 80. to the rightof the piston 88 communicates with the reservoir 28 through a drainpassageway 92.

When lubricant is supplied to the line [8, lubricant pressure builds upin the chamber 40 and the opening 90. The spring 84 and the valve seat88 are proportioned so that a relatively high lubricant pressure, suchasabout 1200 p. s. i., is required to unseat the valve rod 86. Thespring 48 and the piston 42' are proportioned so that a relatively smalllubricant pressure, such as p. s. i., moves the piston 42 downward toseat the venting valve rod 46 and thereby to cut, off communicationbetween the second section 24 of feed line and the sump 28'. The checkvalve spring 66 and ball check; valve 62 are proportioned so that thecheck valve 62 unseats at a relatively small differential lubricantpressure, such as 15 p. s. i., Thus the. venting valve 44 closesv when,the lubricant pressure in the chamber 40' reac es 150. p. s. i., and theadmitting valve. 86 opens rapidly when, the lubricant pressure reachesabout 1200 p. s. i., since the pressure is applied. to the large. areaof the pistorr82 as soon as. the. valve. 86 is unseated. Of course, thislatter pressure is also efiective to open the ballv check valve 62 andpermit lubricant freely to. flow to the second section 24 of the line.The pressure which. builds up, in the passageway 10 However, anadmittingis ineffective .to unseat the. vent valve .44 because the areaof the seat 46 is less. than'the area of the'piston 42.

When the lubricant pressure is released on the line [8, the pressure inthe chamber 40 and the opening 90 decreases. The ball check valve 62closes to prevent reverse flow of lubricant, as soon as forward flowceases, as a result of the fact that the pressure in the passagewayfiurapidly drops below the pressure inthe' second section of feed line24. However, because of the difierence in the areas of the piston 42 andthe venting valve seat 45, the venting valve 44: does not open until thepressure in the chamber 40 drops to some predetermined fraction Oithepressure in the second section 24 of the line.

Although a, relatively great pressure is required to open the valve 86because of the relatively small area of the valve-seat-fifi, a muchsmaller pressure is sufiicient to hold the valve 8'5 open because assoon as the valve is open the lubricant pressure is applied to thepiston 82 which has a relatively great area. For example, the valve 86may not close until a pressure such as 100' p. s. i. is reached.

Before opening, the admitting valve 86 permits a high pressure todevelop in the chamber 40 for positive closing of'the venting valve 44.This construction of the admitting valve 86 minimizes the possibilityof. loss of lubricant from the line 24 to the reservoir 28, duringtheinterval that the pressure in the line section I3 is being built up. Anylubricant which leaks around the piston 82 drains into the reservoir 23.through the passageway 92;

In Fig. 4 another modified iormoi' valve apparatus is illustrated, andcorresponding parts bear the same reference characters as in Fig. l. Thepiston 42, venting valve 44, and ball check valve 62- are substantiallyas described in connection with Fig. 1, except as described hereinafter.The passageway 6.9- communicates directly with the upper portion of thechamber 40. However, the inlet36- from --the first section l8 of theline normally is cut off from the chamber 40-by engagement of anadmitting Valve NW at the end of a piston red as which extends from thetop of the-piston 42, with a plug I52 which forms a seat for the'valve.The spring 48 and the effective areaof the valve [BB are proportioned sothat a relatively high lubricant pressure, such as 1200 p. s. i.,. must,develop inthe line 18 before the valve Hill is unseated and thelubricant is admitted to the chamber 40'. After valve I00 opens andlubricant is admitted to the chamberv 40, the lubricant pressure isexerted on piston 42' which. has a considerably greater area than. thevalve I00, and; the piston is popped downward: rapidly to force theventing valve 44 against its seat 46. A relatively small pressure uponthe piston 42 is suffici'ent to hold the venting valve 44 closed.

The check valve spring 66 and: the check valve 62 are proportioned sothat the valve 62. opens under. a relatively small differential pressuresuch as p. s. i., and after lubricant is admitted to the chamber 4E1-and to the passageway to it flows. freely past the. check valve 52 tothe second. section 24 of the line. The pressure in the line 24 and thepassageway l'il may build up to substantially the same value as thepressure in they section. It of the line without opening the vent.valve. 44 because of the relatively small.

effective area of the vent'valve compared with that of the piston 42.

Closure of. thecheck valve. 62., when. the pressure in. the: line I8 isreleased, prevents theipressure in the line section 24 from. beingmaintained in the chamber 40 and permits the prestrated-. in Fig. 1- isvented, the pressure in the section [8 of: the line dropsv approximatelyexponentially,. rapidly at first but much more slowlyin: the latterstages. Thus the pressure in the remote end: of the line lB- dropsrapidly to a value which. permits the opening of the vent valve 44. Of.course, when the vent valve 44. opens. the pressure at the inlet end ofthe secondsection 24 0f the line drops immediately substantially toatmospheric pressure and the venting: of the second section proceedsmuch more rapidly thanif. the rate ot'venting were limited by therate-of pressure reductionin: the

remote end of the section- |3' Gf-,th8 line. It will be clear that bythe application of the principles of this invention a single feed linelubrication system may be relatively extensive before the ventingtimeotthe system becomes undesirably great- Lubricant may be supplied to thebearings at relatively frequent intervals with the assurance that thefeed-line is properly vented and the metering valves 28 thereby areproperly reconditioned for operation. Alubrication system according tothis invention operates dependably even under severe service conditions.

I.have disclosed thisi-nvention by describing" certain illustrativeembodiments, but it will be clear to those skilled. in the art' that theprinciplesof this-invention may be applied in equivalent waysobtainingsubstantially the same results but differing in detail from theembodiments described herein. Therefore, the details of the abovedisclosurevshould not be construed to limit the-scopeof thisinventionexcept as set forth in the appended claims which, are intended to be acomplete and concise statement of the pa-tentable scope of thisinvention.

I claim:

1. A centralized lubricating system for supplying lubricantpericdi'call'y'to a plurality of bearings, comprising a first. pluralityof measuring valves individually connectedwith some of the bearings. themeasuring valves being operable by" successive application and releaseof lubricant pressure, a first conduit connected with the firstplurality of measuring valves, the first conduit having an inlet and aremote outlet, means al-' ternately to apply and release lubricantpressure at: the inlet of the first conduit, a second plurality ofsimilar measuring valves located remotely from. the. inlet. of; thefirst conduit, a sec" ond .c'onduiti connected with the second pluralityofmeasuring valves, atventoutlet, aventing'valve connected between thesecond conduit and the vent outlet normally providing a relief passageto: transmit lubricant from. the: second conduit to: the vent outlet,3;. pressure sensitive device in the valve to close the latter, meansconnecting the device to the outlet of the first conduit for.

closing the valve in response to pressure therein,

and means including a check valve connecting the outlet of the firstconduit to the second conduit to transmit lubricant under a substantialpressure from the first conduit to the second, but to prevent reverseflow of lubricant.

2. A centralized lubricating system for supplying lubricant periodicallyto a plurality of bearings, comprising a first plurality of measuringvalves individually connected with some of the bearings, the measuringvalves being operable by successive application and release of lubricantpressure, a first conduit connected with the first plurality ofmeasuring valves, the first conduit having an inlet and a remote outlet,means alternately to apply and release lubricant pressure at the inletof the first conduit, a second plurality of similar measuring valveslocated remotely from the inlet of the first conduit, a second conduitconnected with the second plurality of measuring valves, a vent outlet,a venting valve connected between the second conduit and the ventoutlet, a spring in the valve normally opening the latter to provide arelief passage to transmit lubricant from the second conduit to the ventoutlet, a pressure sensitive device in the valve to close the latter,means connecting the device to the outlet of the firstconduit forclosing the valve in response to pressure therein,

and means including a check valve connecting the outlet of the firstconduit to the second conduit to transmit lubricant under a substantialpressure from the first conduit to the second, but to prevent reverseflow of lubricant.

3. A centralized lubricating system for sup-- plying lubricantperiodically to a plurality of bearings, comprising a first plurality ofmeasuring valves individually connected with some of the bearings, themeasuring valves being operable by successive application and'release oflubricant pressure, a first conduit connected with the first pluralityof measuring valves, the first conduit having an inlet and a remoteoutlet, means alternately to apply and release lubricant pressure at theinlet of the first conduit, a second plurality ofsimilar measuringvalves located remotely from the inlet of the first conduit, a secondconduit connected with the second plurality of measuring valves, a ventoutlet, a ventin valve connected between the second conduit and the ventoutlet normally providing a relief pasease to transmit lubricant fromthe second conduit to the vent outlet, a differential pressure sensitivedevice in the valve to operate the latter, means connecting the deviceto the outlet of the first conduit for closing the valve in response toan excess of pressure therein over the pressure in the second conduit,the differential pressure sensitive device being arranged to open thevalve in response to a substantial eXcess of pressure in the secondconduit over that in the first conduit, and means including a checkvalve connecting the outlet of the first conduit to the second conduitto transmit lubricant under a substantial pressure from the firstconduit to the second, but. to prevent reverse fiow of lubricant.

4. A centralized lubricating system for supplying lubricant periodicallyto a plurality of bearings, comprising a first plurality of measuringvalves individually connected with some of the bearings, the measuringvalves being operable by successive application and release of lubricantpressure, a first conduit connected with the first plurality ofmeasuring valves, the first conduit having an inlet and a remote outlet,means alternately to apply and release lubricant pressure at the inletof the first conduit, a second plurality of similar measuring valveslocated remotely from the inlet of the first conduit, a second conduitconnected with the second plurality of measuring valves, .a vent outlet,a venting valve connected between the second conduit and the vent outletnormally providing a relief passage to transmit lubricant from thesecond conduit to the vent outlet, a pressure sensitive device in thevalve to close the latter, means connecting the device'tothe outlet ofthe first conduit for closing the valve in response to pressure therein,and means including a valve connecting the outlet of the first conduitto the second conduit to transmit lubricant under a substantial pressurefrom the first conduit to the second, the last mentioned valve includinga valve closing plug arranged to be opened by pressure in the firstconduit and a spring urging the plug to valve closing position.

5. A centralized lubricating system for supply ing lubricantperiodically to a plurality of bearings, comprising a first plurality ofmeasuring valves individually connected with some of the bearings, themeasuring Valves being operable by successive application and release oflubricant ressure, a first conduit connected with the first plurality ofmeasuring valves, the first conduit having an inlet and a remote outlet,means alternately to apply and release lubricant pressure at the inletof the first conduit, a second plurality of similar measuring valveslocated remotely from the inlet of the first conduit, a second conduitconnected with the second plurality of measuring valves, a vent outlet,a venting valve connected between the second'conduit and the vent outletnormally providing a relief passage to transmit lubricant from thesecond conduit to the vent outlet, a pressure sensitive device in thevalve to close the latter, an admitting valve having an inlet and anoutlet end, the inlet end being connected to the outlet of the firstconduit, the pressure sensitive device being con nected to one of theends of the admitting valve, the admitting valve including a valve plugmovable by predetermined pressurein the inlet end to open the valve anda sprin urging the plug to closed position, and a check valve connectedbetween the outlet end of the admitting valve and the second conduit totransmit lubricant from the first conduit to the second.

6. A centralized lubricating system for supplying lubricant periodicallyto a plurality of bearings, comprising a first plurality of measuringvalves individually connected with some of the bearings, the measuringvalves being operable by successive application and release of lubricantpressure, a first conduit connected with the first plurality ofmeasuring valves, the first conduit having an inlet and a remote outlet,means alternately to apply and release lubricant pressure at the inletof the first conduit, a second plurality of similar measuring valveslocated remotely from the inlet of the first conduit, a second conduitconnected with the second plurality of measuring valves, a vent outlet,a venting valve connected between the second conduit and the vent outletnormally providing a relief passage to transmit lubricant from thesecond conduit to the vent outlet, a pressure sensitive device in thevalve to close the latter, means connecting the device to the outlet ofthe first conduit for closin the valve in response to pressure therein,an admitting valve having an inlet connected to the outlet oi'the firstconduit, and acheck valve connected between the admittin valve and thesecond conduit to transmit lubricant to the second conduit, theadmitting valve having a valve closing plug arranged to be opened bypredetermined pressure in the first conduit and a spring urging the plugto closed position, the admitting valve spring being strong enough tohold the admitting valve closed until after the venting valve is closed.

7. A centralized lubricating system for supplying lubricant periodicallyto a plurality of bearings, comprising a first plurality of measuringvalves individually connected with some of the bearings, the measuringvalves being operable by successive application and release of lubricantpressure, a first conduit connected with the first plurality ofmeasuring valves, the first conduit having an inlet and a remote outlet,means alternately to apply and release lubricant pressure at the inletof the first conduit, a second plurality of similar measuring valveslocated remotely from the inlet of the first conduit, a second conduitconnected with the second plurality of measuring valves, a vent outlet,a combined venting and admitting valve providing a first valved passageconnected between the second conduit and the vent outlet and a secondvalved passage connected with the outlet of the first conduiha pressureresponsive movable member having-a vent valving part and an admittingvalve plug at its opposite ends positioned to close the respective firstand second passages alternately, a spring urging the member to aposition for closing the second passage, the member being shiftable bypredetermined pressure in the .outlet of the first conduit to-a positionfor closing the first passage, and a check valve connected between thesecond passage and the second conduit to transmit end and an outlet end,the inlet end being connected to the source of lubricant pressure, thepressure sensitive device being connected to one or the ends of theadmitting valve, the admitting valve including a valve plug movable bypredetermined pressure in the inlet end to open the valve and a springurging the plug to closed position, and a check valve connected betweenthe outlet end of the admitting valve and the conduit, to transmitlubricant thereto.

9. In a centralized lubricating system having a plurality of feedervalves operable by successive application and release of lubricantpressure, a lubricant conduit connected to the valves. and anintermittently operable source of lubricant pressure; a vent outlet, aventing valve connected between the conduit and the vent outlet normallyproviding a relief passage to transmit lubricant from the conduit to thevent outlet, a pressure sensitive device in the valve to close thelatter, means connecting the device to the source of lubricant pressurefor closing the valve in response to pressure therein, an admittingvalvehaving an inlet connected to the source of lubricant pressure, anda check valve connected between the admitting valve and the conduit totransmit lubricant thereto, the admitting valve having a valve closingplug arranged to be opened by predetermined pressure of the source and aspring urging the plug to closed position, the admitting valve springbeing strong enough to hold the admitting valve closed until after theventing valve is closed.

10. In a centralized lubricating system having a plurality of feedervalves operable byv successive application and release of lubricantpressure, a lubricant conduit connected to the valves, and anintermittently operable source of lubricant pressure; a vent outlet, acombined venting and admitting valve providing a first valved passageconnected between the conduit and the vent outlet, and a second valvedpassage connected with the source of lubricant pressure, a pressureresponsive movable member having a vent valving part and an admittingvalve plug at its opposite ends positioned to close the respective firstand second passages alternately, the spring urging the member to aposition for closing the second passage, the member being shiftable bypredetermined pressure of the source to a position for closing the firstpassage, and a check valve connected between the second passage and theconduit to transmit lubricant thereto.

HARRY R. TEAR. 1

REFERENCES CITED The follbwing references are of record in the file ofthis patent:

UNITED STATES PATENTS

